In general, when document information in a document management system is transmitted by an electronic mail application, the document information itself or the result of expanding the document into an image having a certain format is transmitted.
However, if the amount of data of the document perse that is to be transmitted is large, a great load is placed upon the electronic mail system. Regarding an image document stored in the document management system, it is possible to add additional information such as annotation information and user's own property information to expanded data. However, when an actual document is attached to an electronic mail, it is not easy to display an actual document and its additional information with explicit indication of the relationship between them. If the actual document can be referred in the format or state in which it was stored in the document management system, the above problem will be solved. However, in order to perform the above operation, it is necessary to ascertain the storage location of the document through a different method and the procedure involved is troublesome.
Furthermore, in a case where the document is referred to in the format in which it was stored in the document management system, there are instances where user registration is necessary in order to access the system in which the document exists. The result is poor operability.